Pavel Smirnov questions

Pavel Smirnov answers

• How SQL would handle multiple process writes the same record into the same database table simultaneously?
• Mock Instant.now() without using Clock into Constructor or without Clock Object
• Map of generics: read and write
• What is the importance of abstract class that extends from another abstract class
• What is the difference between Java intrinsic and native methods?
• ANTLR 4 - Mismatched input
• jdk 8 run empty main function , why PSYoungGen already used about 1000k space
• Java concurrency : Do I have to synchronise a method that only retrieve state and does not modify it?